Light-projecting device.



0. R. FORSTER.

Patented Jun 14,1910.

3 SHEETS-SHEET 1.

G. R. FORSTER. LIGHT PROJEGTING DEVICE. APPLIOATION FILED MAR. 25, 1904.

Patented June 14,1910.

3 SHEETS-SHEET 2- fn 'veat'or C. RJFORSTER.

LIGHT PROJEGTING DEVICE.

APPLICATION FILED 111112.25, 1904.

W2 Z n asses [raven/Z011 tweenthe carbons of the are light.

UNITED STATES PATENT orrien.

CARL R. FORSTER, OF EVANSTON ILLINOIS.

LIGHT-PROJECTING DEVICE.

Specification of Letters Patent.

Patented June 14, 1910.

Application filed narcii 25, 1904, Serial No. 200.027.

To all whom it may concern:

Be it known that I, CARL R. F ORSTER, a citizen of the United States, residing at with a. view to meeting the particular requirements of theater or stage use where it is desirable to produce color effects and dimming or changes.v from light to dark- DGSS.

One of the objects of the invention is to provide a device of this character whereby easy and gradual changes may bemade in the color of a light projected from a light or lamp similar to the effect which has heretofore been produced by'the use of millticolor incandescent lamps used in connection with rhcostats or dimmers;

A further object of the invention is to produce a gradual dimming or lessening of the intensity of the light projected in the manner as herein set forth.

A still further object of the invention is to produce the gradual color change and dimming effect of a plurality of lamps synchronously and simultaneously, yet a further object of the invention is to provide a device of this characterwhich shall be entirely fireproof, and which will not ignite surrounding; objects.

ll' ith'these ends. in viewiny invent-ion consists in certain features of novelty in the construction, combination and arrangement.

of parts by which the said objects and certzllll other objects hereinafterappearing are attained, 'all as fully described with reference to the accompanying drawings and more particularly pointed out in the claims.

In the said drawings,-Figure 1 is a front elevation of my improved projecting device, with the shield and color globe partially broken away to show the interior arrangement. Fig. 2' is apartial side elevation and partial vertical} section thereof- Fig. 3 is a. horizontal section, taken in a plane be- Fig. l is a front view of a projector in which the reflector is slotted to receive the carbon holders. Fig. 5 is a vertical section of the construction shown in Fig. 4:, showing in addition thereto a supplemental mirror or reflectingsurface. Fig. 6 is an enlarged view of the color globe and screen, partially broken away to show the interior arrangement. Fig. 7 is a diagrammatic view illustrating a convenient mode of rotating the color globe- Fig. 8 illustrates diagraman undulating body forming separated lenses through which the light passes directly to the object or surface to be illuminated. Figs. i) and 10 are, av fragmentary view and a sectional view, respectively, of a form of reflector or mirror for breaking up the reflected light and blending the colors. Figs. 11 and are similar views of a modified form of reflector. Fig. 13 a diagrammatic view of a stage arrangement, showing series of lamps arranged about the stage and connected with a device for synchronously operating the color. globes of all' the lamps.

In carrying myinvention into effect I may employ either a reflected or direct light. I have herein shown my improved projector in connection with an electric are light, though anylight of the required intensity may be used.

As shown in the drawing, A designates a reflector which may be made of any shape to suit the use and application to which it may be put.

13 B designates the lamp carbons which are carried on the forward ends of the horizontal arms J of holders L, and said holders are connected with a feeding mechanism, indicated diagrammatically at M. Such fceding mechanism inay be either automatically 'or manually operable. The reflector is shown as attached centrally to the box containing the feeding mechanism.

D designates a transparent. rot-ative color globe which incloses the adjacent or active ends of the carbons B. Said globe is made of a plurality of parts of different colors, the several parts being shown as divided in lines which are in vertical planes passed through the axis of rotation of the globe. The globe is shown as made of three parts, 1, 2 and 3, (Fig. 3), each including, as herein shown, one-third of the globe. The different parts matically the projecting device con'iprisiiig' ca rb of the globe are made of different colors, as

forinstance, the part 1 may be red, the part :2 blue, and thepart 3 white. Fig. 6 illustrates more clearly the construction of the multicolored globe which incloses active ends of the carbons I3. The carbons enter the globe at an angle to the axis of rotation thereof, meeting near the rear side of the globe. In this manner, more-of the crater light is directed to the reflector or mirror A than if the carbons approached each other in alinement. The said carbons pass through bushings I. and O seated in upper and lower openings of the globe. The bushings are stationary and close joints are formed between the same. and the carbons and between the outer surfaces of the bushings and the openings in which they are contained. The openings in the upper and lower ends of the globe are surrounded by rims (Z (P. The upper bushing I fits within the upper rim. The lower bushing O is contained within a central opening in a gear E 'which extends upwardly into'the lower rim (1 of the bushing, said gear E being attached to the globe in any suitable manner for the purpose of rotating the globe. The bushings 1 and O furnish stationary supports for the carbons and also prevent free access of air fto the globe and prevent rapid combustion of the ons.

As shown in the principal figures of the drawing, the'light ofthe lamp is transmitted to the object or scene to be illuminated through the mediumof the reflector A. The part of the globe on the side remote from the reflector 'is covered by a partispherical-shaped screen C, the relative position of whiehito the globe is more clearly shown in Fig. 3. This screen is provided at its upper andlower margins with rims ccwhic'lieonform generally to the shape of the rimsd d of the globe, and the lower rim 0 rests upon the upper faceof the gear E (Fig. 6). Said screen is attached to the reflector A by means of radialhorizontal .arms K K,

fore stated, may be manually effected, or;

may be placed under automatic control. As herein shown, such rotation is effected by an electrical apparatus governed bya metronome Q, the vibratory member T of which closes a normally open circuit by contact of said part T with a spring contact S. Said circuit embraces, in addition to a battery S two magnets U U. f

V designates an armature which is attracted to the magnets when the latter are energized. Said armature is attached to a pivoted lever W which is provided with a pawl X that engages the ratchet teeth R are normally held away from the magnets U by a spring Y against a stop Y and the pawl X is heldspring-pressed againstthe ratchet teeth R by means of a spring w. Whengthe magnets are energized the armature and lever are drawn toward the magnets, thereby effecting, through the medium of the pawl X, one step of the rotation of the wheel H .and shaft G, and, by reason of the gearing described, rotating the multicolored globe one step. The proportion of the pinion F and gear E is such that a. one step movement of the pinion produces but a slight rotary movement of the globe, so that the latter rotates but slowly as com pared to the movement of the'vibra-tory part of the metronome.

In some instances, a dimmer X (Fig. '3) is located between the color globe and the screen, said dimmer acting to gradually cut off the light from the reflector as it is turned from the posit-ion shown in said Fig. 3 toward the screen in either direction. Any suitable means may be provided for rotatirfiig the dimmer and such rotation may be e ected by hand or in synchronism witli rotation of the globe.

In Figs. e and 5 I have shown the reflectorA as provided, in line with the carbon holders, with slots a to receive-the holder arms J' as the same are moved towardeach other in feeding the carbons. This construction makes it unnecessary to use such viously' described. In'such previously. described construction the inward movement of the wheel H. The armature and'the arm long'carbons, as in the construction preof the carbons is limited by the contact of I the holder arms J with the margins of the reflector so that there is a length of carbon and which would otherwise be obscured by the globe and its screen, in such manner. that it is thrown upon the illuminated scene. This supplemental surface Pisso shaped as to reflect the light which strikes it from the globe to the outer parts of the mirror or reflector whence it is reflected to the illuminated scene or object. This arran ement enables me to use a somewhat smaller reflector surfaces for the purpose.

Figs. 11 and 12 the surface is broken up by actuating magnets U of the several devices Hector A while projecting practically the same volume of light.

The reflecting surface of the reflector or mirror A is preferably broken up in such manner that the color rays reflected therefrom when two or more colors are reflected will be broken up and instead of striking the illuminated scene or object as they are thrown 'upon the screen. the colors of the rays are broken up or blended so that the color produced is resultant of the two or more colors projected from the lamp. I have shown in Figs. 9 to 12, inclusive, re-

Iii Figs. 9 and 10 the surface of the reflector is shown as provided with a. plurality of depressions a, the curvature of which approximatesa parabola, each depression constituting in effect a separate or distinct reflector or niirror covering-practically all the scene .to be illuminated. In the construction shown in a plurality of concentric groovesa The same general etfect may be produced by frosting the mirrors instead of indenting the surface as shown. I may also employ, instead of a mirror, the direct rays of the lamp,,in which event, in order to blend two or more colors projected through the globe, the color rays are passed through a series of connected lenses A as shown in Fig. 8. Said lenses are so arranged as to perfectly diffuse and blend the multicolored light rays. Further the rays may be projected. by a reflector located inside the globe behind the light and throwing the rays directly upon the scene through the color globe.

In Fig. 13 I have shown diagrammatically means for connecting a series of lamps with a single metronome or other suitable central station operating device whereby all of the color globes and dimmers or either of a number of lamps may be operated in synchronism and thereby project the light upon a scene from a number of lamps located in different parts of the stage. In said figure, the globe D is shown separated from the lamp, instead of inclosing the same, in order 7 to more clearly indicate the electrical con- 'nections with the severed globe. All of the are connected in a circuit which is closed by a single metronome Q. or other circuit closing device. In operating a series of lamps and projectors in this manner all of the globes may be set to produce the same illuminating effect with respect to color as the others, or a varying color effect may be produced by adjusting the globes before starting the same to show several different colors. Other devices than electrical devices may be employed for operating a series of lamps in the manner stated.

The operation of the projector constructl by referenceto .Fig. 3

when one of the color sections, 1, 2 or 3, of

v fore,

.mary colors reflected upon the scene.

ed as described is generally as follows, reference being had, first, to the reflecting or mirror type of the device. It willbe noted of the drawing that the globe is turned directly toward the re flector A, the section 2. as herein shown. the screen C is so related thereto and isof such length that all ihe'lightwnich strikes said reflector A passes through the section of the globe 2 turned directly toward the reflcctor. Under these circumstances, thereall the light directed upon the illuminated scene or object is of a single color. llpon turning the globe in either die rcction the light from the next adjacent section, and of a different color, falls upon the reflector and is reflected upon theilluminated scene. If a true parabolic curve be used and with a smooth reflecting surface the result of casting two colors upon the reflector would be that two colors would be cast upon the illuminated scene with a reasonably sharp line ofdemarcation between them. By breaking up thereflecting surface, however, as shown in Figs. 9 to 12, inclusive, or otherwise, the colors falling upon the screen are so-blended as to produce, instead of the original or primary colors, a resultant color which at any given time depends upon the proportions of the pri- As said globe is gradually turned through a single rotation the resultant light from the multi-colored sections of the globe produces a" gradually changing effect upon the illuminated scene the specific effect or color of which will depend upon the colors employed and their proportions in the blending or. diffusion thereof. For instance, by'the proper arrangement of the colorson the globe sections the light of the illuminated scene may be changed from a bright light, as

a daylight scene or a brightmoonlight scene, I

to a twilight scene, or a .night scene or vice versa; and the efiects are such that desired extravaganza productions may be variedalmost infinitely.

The device as herein shown and as here-' tofore described is particularly adapted to produce what is known as glow-light and the globe to revolve it, yet, in" many in stances, the changes in the color of the light to be thrown upon an illuminated scene will necessarily be made by hand manipulation of the device. I

The operation of the device shown in Fig.

v 110 and sought for effects in stage lighting for 8 is in all substantial respects the same as that just described the only difierence being that'the light passes directly to the scene being illuminated instead of being reflected thereupon and the lens of the series acts to breakup or diffuse the color-rays so 'as to produce the desired resultant colors.

'When it is desired to dim the illuminated scene, the dimmer X is rotated so as to exclude a portion of the light" from the screen or'from the lenses, as the case may be, there by lessening the intensity of the volume of light thrown uponthe scene. It is to be understood that the dimmer does not have the effect of entirely excluding the light from any part of the scene, inasmuch as the arrangement of the reflector, or the lenses, as the case may be, is such that the light from all parts of the reflector is diffused over the entire scene, so that when a portion of the light is cut off by thedimmer it only results in dimming the general effect and not excluding light entirely from a part of the scene.

In all of the constructions described it will be noted that the are is entirely inclosed f within the globe so that there is no danger of surrounding objects, such as draperies,

becoming ignited by contact with the flame of the arc-nor is there any possibility of' sparks passing from the arc to exterior objects. The device is therefore fireproof;

It is ."obvious that a partial globe, or one I that does not extend entirely around, the

lamp, ifmade of different colored sections,

will produce the same effect when interposed between the lamp and a reflector'or a series of lenses, with the exception that the effect produced thereby will be interrupted by the interruption of the globe. The continuous globe is preferred inasmuch as-its movement maybe continuous and a gradually unbroken light effect produced.

' Claims.

1 In a device for the purpose described, the combination of a light projecting device,

I a screen arranged in front of said light projecting device, a source of light arranged between said screen andpro ectlng device, and

a spherically formed color medium extending about the source of light and interposed between the said source of light and projecting device and adjustable about the said.

source of light.

- 'a. screen arranged in front of said light prosaid screen and projecting device and a rojecting device, a lamp interposed between tative globe inclosing said lamp.

3. In a device for the purpose described, the combination of a light projecting device having a concave, roughened surface, a

screen opposed to said surface, a source of 2. In'a device for the purpose described, the combination of a light projecting device,

light interposed between said screen and surface, and a multicolor medium interposed between said source of. light and surface.

.4. The combination with a lamp, of a reflector in rear thereof, having a broken or roughened reflecting surface, a rotative multicolored globe interposed between the lamp and reflector, and a screen inclosing the lamp on the side thereof remote from-the reflector.

5. The combination with a lamp, of a reflector in rear thereof, having a broken or roughened reflecting surface, a 'rotative, multicolored globe interposed between the lamp and reflector, a screen inclosing the lamp on the side thereof remote from the reflector and a movable dimmer interposed u between said screen and lobe.

6. The combination with the carbons of \an electric arc lamp, of a rotative, transparent globe inclosing. the meeting ends of the carbons, stationary bushings provided with openings through which the carbons pass and themselves located in openings in said globe, said globe being made of sections of diflerent colors, and a projecting device for throwing the light passed through said color globe upon a desired scene or object,

an electric arc lamp, of a rotative globe'in closing the meeting ends of said carbons and composed of a plurality of sections of different colors, a reflector in rear of'the. globe and constructed to break up and diffus'e the color rays, a screen in front of the globe, and a dimmer interposed between said screen v8. The combination with the carbons .of

and globe and adapted to be moved "about the, globe.

9. The combination with the carbons of an electric arc lamp, of a globe. surrounding the meeting ends of said carbons and ,com'-- posed of, a plurality of sections of different colors, said carbons being directed obliquely toward the rear side of said globe, a re-- fiector in rear of said globe, and a screen on I .the side of the carbons remote from the reflector, said reflector being constructed to blend the color rays from said globe. j

10. The combination with the carbons of an electric arc lamp, of a rotative globe inclosing the meeting ends of said carbons and composed of a lurality of sections of different colors, a re ector in the rear of the globe and a screen located in the'front of the globe.

11. The combination with the carbons of the meeting ends of said carbons and coman electric arc lamp, of a rotating globe inposed of a plurality of sections of dillerent closing the meeting ends of said carbons and colors, said. carbons being; directed obliquely composed of a plurality of sections of differtoward the rear side of said globe, a reflector ent colors, a reflector in the rear of the globe in the rear of said globe, and a screen on the 15 a. screen in front of the globe, and a dimmer side of the carbons remote from the reflector.

interposed between said screen and globe and CARL R. FORSTER. adapted to be moved about the globe. X Vit s;

12. The combination with the carbons of c F. A. HoP INs,

10 an electric arc lamp, a globe surrounding M. B. ALLsTAoT. 

